THE FATIGUE CONSTITUTIVE MODEL OF CONCRETE BASED ON MICRO-MESO MECHANICS

In this paper we focus on the explanation of concrete fatigue damage on micro-meso-scales. Base on the rate process theory, the physical meaningful expression of fatigue damage energy dissipation is built on meso-scale with considering the dynamic effect of water molecules in the fracture process zone. Combing with meso-stochastic fracture model, the fatigue damage evolution equation is acquired under the framework of macro-damage mechanics. The fatigue damage evolution curve and fatigue life under various loading levels in uniaxial tension are computed with numerical simulation and the comparisons with test results show that the model proposed here gives a correct description of fatigue damage evolution process of concrete.